The exclusions cover materials that are not solid wastes, solid wastes that are not hazardous wastes, hazardous wastes that are exempt from certain regulations, and samples associated with chemical and physical testing or treata-bility studies. For regulatory purposes, the following are not considered solid wastes:

Domestic sewage, or any mixture of domestic sewage and other wastes, passing through a sewer system to a publicly-owned treatment works Industrial wastewater point discharges regulated under

Section 402 of the Clean Water Act Irrigation return flows

Source, special nuclear, or by-product material as defined by the Atomic Energy Act of 1954, as amended Materials subject to in situ mining techniques but not removed from the ground as part of the extraction process Pulping liquids that are reclaimed in a pulping liquor recovery furnace and reused in the pulping process Spent sulfuric acid used to produce virgin sulfuric acid Secondary materials that are reclaimed and, with certain restrictions, returned to their original generation process(es) and reused in the production process Spent wood-preserving solutions that are reclaimed and reused for their original intended purpose Wastewaters from the wood-preserving process that are reclaimed and reused to treat wood Listed hazardous wastes from coking and coke by-products processes that are hazardous only because they exhibit toxicity characteristics when, after generation, they are (1) recycled to coke ovens, (2) recycled to the tar recovery process as a feedstock to produce coal tar, or (3) mixed with coal tar prior to the tar's sale or refining Nonwastewater splash condenser dross residue resulting from treating emission control dust and sludge in high-temperature metals-recovery units in primary steel production (a listed waste)

The following solid wastes are not considered hazardous by the RCRA regulations:

Household wastes, including garbage, trash, and sanitary wastes in septic tanks Solid wastes generated in growing and harvesting agricultural crops or raising animals; this includes animal manures that are returned to the soil as fertilizers Mining overburden returned to the mine site Fly ash waste, bottom ash waste, slag waste, and flue gas emission control waste, generated from coal or other fossil fuels combustion

Drilling fluids, produced waters, and other wastes associated with the exploration, development, or production of crude oil, natural gas, or geothermal energy Waste that could be considered hazardous based on the presence of chromium if it can be demonstrated that the chromium is not in the hexavalent state. Such a demonstration is based on information showing only trivalent chromium in the processing and handling of the waste in a non-oxidizing environment, or a specific list of waste sources known to contain only trivalent chromium.

Solid waste from extracting, beneficiating, and processing of ores and minerals Cement kiln dust waste, unless the kiln is used to burn or process hazardous waste

Before an environmental engineer concludes a company or concern is not subject to regulation under RCRA, the engineer should confirm this conclusion via the RCRA Hotline (1-800-424-9346). Preferably, the decision should also be confirmed by an attorney or other qualified professional familiar with RCRA regulations.